Rotatable mounting fixture for a lamp



FIG. 1 is a perspective view rotatable mounting fixture for a lamp showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a perspective view thereof after having been rotated with respect to its base; and,

FIG. 5 is a perspective view thereof with a panel removed. 

The ornamental design for a rotatable mounting fixture for a lamp, as shown and described. 